Ties

Abstract:Recent research suggests that the genotype of one individual in a friendship pair is predictive of the genotype of his/her friend. These results provide tentative support for the genetic homophily perspective, which has important implications for social and genetic epidemiology because it substantiates a particular form of gene-environment correlation. This process may also have important implications for social scientists who study the social factors related to health and health-related behaviors. We extend this work by considering the ways in which school context shapes genetically similar friendships. Using the network, school, and genetic information from the National Longitudinal Study of Adolescent Health, we show that genetic homophily for the TaqI A polymorphism within the DRD2 gene is stronger in schools with greater levels of inequality. Our results suggest that individuals with similar genotypes may not actively select into friendships; rather, they may be placed into these contexts by institutional mechanisms outside of their control. Our work highlights the fundamental role played by broad social structures in the extent to which genetic factors explain complex behaviors, such as friendships.

Abstract:From a policy standpoint, the spread of health conditions in social networks is important to quantify, because it implies externalities and possible market failures in the consumption of health interventions. Recent studies conclude that happiness and depression may be highly contagious across social ties. The results may be biased, however, because of selection and common shocks. We provide unbiased estimates by using exogenous variation from college roommate assignments. Our findings are consistent with no significant overall contagion of mental health and no more than small contagion effects for specific mental health measures, with no evidence for happiness contagion and modest evidence for anxiety and depression contagion. The weakness of the contagion effects cannot be explained by avoidance of roommates with poor mental health or by generally low social contact among roommates. We also find that similarity of baseline mental health predicts the closeness of roommate relationships, which highlights the potential for selection biases in studies of peer effects that do not have a clearly exogenous source of variation. Overall, our results suggest that mental health contagion is lower, or at least more context specific, than implied by the recent studies in the medical literature.

Abstract:Chimpanzees exhibit cultural variation, yet examples of successful cultural transmission between wild communities are lacking. Here we provide the first account of tool-assisted predation ("ant fishing") on Camponotus ants by the Kasekela and Mitumba communities of Gombe National Park. We then consider three hypotheses for the appearance and spread of this behavior in Kasekela: (1) changes in prey availability or other environmental factors, (2) innovation, and (3) introduction. Ant fishing was recognized as habitual in the Mitumba community by 1992, soon after their habituation began. Apart from one session in 1978, Camponotus predation (typically with tools) was documented in the Kasekela community beginning only in 1994, despite decades of prior observation. By February 2010, ant fishing was customary in Kasekela and with one exception was practiced exclusively by chimpanzees born after 1981 and immigrant females. We hypothesize that changes in insect prey availability over time and/or the characteristics of one popular ant-fishing site may have influenced the establishment of ant fishing. Though innovation cannot be completely ruled out, the circumstantial evidence suggests that a Mitumba immigrant introduced ant fishing to Kasekela. We submit that this report represents the first documented case of successful transmission of a novel cultural behavior between wild chimpanzee communities.

Abstract:Loneliness has been shown to longitudinally predict subjective well-being. The authors used data from a longitudinal population-based study (2002-2006) of non-Hispanic white, African-American, and nonblack Latino-American persons born between 1935 and 1952 and living in Cook County, Illinois. They applied marginal structural models for time-varying exposures to examine the magnitude and persistence of the effects of loneliness on subjective well-being and of subjective well-being on loneliness. Their results indicate that, if interventions on loneliness were made 1 and 2 years prior to assessing final subjective well-being, then only the intervention 1 year prior would have an effect (standardized effect = -0.29). In contrast, increases in subjective well-being 1 year prior (standardized effect = -0.26) and 2 years prior (standardized effect = -0.13) to assessing final loneliness would both have an effect on an individual's final loneliness. These effects persist even after control is made for depressive symptoms, social support, and psychiatric conditions and medications as time-varying confounders. Results from this study indicate an asymmetrical and persistent feedback of fairly substantial magnitude between loneliness and subjective well-being. Mechanisms responsible for the asymmetry are discussed. Developing interventions for loneliness and subjective well-being could have substantial psychological and health benefits.

Abstract:Gossip has been related to friendship as it can increase the bond between people and sense of belonging to a group. However, the role of gender in the relationship between gossip and friendship has not been examined in the literature. So, the present study examined gender differences in the relationship between friendship quality and gossip tendency with a sample of 167 female and 69 male Western Canadian undergraduate University students using the Friendship questionnaire and the Tendency to Gossip questionnaire. Given gender differences in friendship, with males being more agentic and females more communal, the relationship between gossip and friendship was predicted to be stronger in the males compared to the females. Friendship quality was positively correlated with gossip tendency in the males, but this effect was not present with the females. The information gossip scale was strongly associated with male friendship quality. This finding may be related to the greater emphasis on status with males, and that possession of knowledge and control of information is a method of attaining status. Physical appearance gossip was found to be more prevalent in females, but not related to friendship quality. This type of gossip may be a more of a competitive threat to the relationship in females. Achievement related gossip was also related to male friendship quality, which reflects the greater emphasis on individuation in male friendships.

Abstract:This paper builds on the general connection between culture consumption and sociability which has been the focus of recent research in the sociology of culture. I propose that cultural variety, as given by the number of cultural activities that the person engages in, is tied not only to static properties of social networks (such as range), but also to the likelihood of having benefited from this connectivity (social capital). Taking the classic example of finding a job via a network contact as the main outcome, I show that persons who have a propensity to engage in a wide variety of cultural activities have a higher likelihood of having found out about their current job via a weak tie and that different types of weak tie activation are selectively correlated with distinct cultural taste profiles.

Abstract:The basis on which people make social judgments from the image of a face remains an important open problem in fields ranging from psychology to neuroscience and economics. Multiple cues from facial appearance influence the judgments that viewers make. Here we investigate the contribution of a novel cue: the change in appearance due to the perspective distortion that results from viewing distance. We found that photographs of faces taken from within personal space elicit lower investments in an economic trust game, and lower ratings of social traits (such as trustworthiness, competence, and attractiveness), compared to photographs taken from a greater distance. The effect was replicated across multiple studies that controlled for facial image size, facial expression and lighting, and was not explained by face width-to-height ratio, explicit knowledge of the camera distance, or whether the faces are perceived as typical. These results demonstrate a novel facial cue influencing a range of social judgments as a function of interpersonal distance, an effect that may be processed implicitly.

Abstract:The current study investigated the effect of distance on medium preferences in interpersonal communication. Five experiments showed that people's preference for using pictures (vs. words) is increasingly higher when communicating with temporally, socially, or geographically proximal (vs. distal) others. In contrast, preference for words is increasingly higher when communicating with those who were distal. A sixth experiment showed that communication's medium influences distance preferences, such that people's preference for communicating a message to a distant (vs. proximal) target is greater for verbal compared with pictorial communications. A seventh experiment showed that recipients are more likely to heed a sender's suggestions when the medium and distance are congruent. These findings reflect the suitability of pictures for communication with proximal others and words with distal others. Implications of these findings for construal-level theory, perspective taking, embodied cognition, the development of language, and social skills with children are discussed.

Background: People with larger social networks are known to have better well-being; however, little is known about (1) the association with socio-demographic factors that may predict the size and composition of social networks and (2) whether the association with well-being is independent of pre-existing psychological health or socio-demographic factors.

Methods: The authors used information collected from 3169 men and 3512 women who were born in Great Britain in 1958. First, age on leaving full-time education, partnership and employment status at age 42 were used to predict the size and composition of cohort members' social networks at age 45 using ordered logistic regression. Second, using multiple linear regression, the associations between social network size by composition (relatives and friends) and psychological well-being at age 50 were assessed, adjusting for socio-demographic factors and psychological health at age 42.

Results: Not having a partner and staying in full-time education after age 16 was associated with a smaller kinship network in adults. Having a smaller friendship network at age 45 was associated with poorer psychological well-being among adults at age 50, over and above socio-demographic factors and previous psychological health. Additionally, having a smaller kinship network was associated with poorer psychological well-being among men.

Conclusions: Having a well-integrated friendship network is a source of psychological well-being among middle-aged adults, while kinship networks appear to be more important for men's well-being than for women's. These relationships are independent of education, material status and prior psychological health.

Abstract:As with standard models of rationality, theorists generally treat prospect theory's demonstration of risk aversion in gains but risk tolerance in losses as domain-general. Yet evolutionary psychology suggests that natural selection has designed a domain specific cognitive architecture - with systems specialized for some substantive domains but not others. Here we address risky choices through that lens asking whether humans' risk responses dispose them to enter social relationships even when doing so is counter to normative rationality and regardless of whether the "enter" versus "not enter" choice is framed as between gains and losses. Laboratory findings in five sites across three countries provide a positive answer to both possibilities. Participants could enter or not enter inherently risky social relationships. They were more willing to enter such relationships than rational choice models would predict and were equally so willing regardless of whether equivalent alternatives were framed as gains and as losses. With the "social context" extracted in otherwise identical games, participants' risk responses were consistent with prospect theory. The present findings suggest the possibility of adaptations designed to facilitate sociality - despite its risks and how those risks are framed.

William Hart & Alex BurtonJournal of Experimental Social Psychology, forthcoming

Abstract:Behavior can be identified in terms of purpose/meaning (high-level behavior identities) or mechanics (low-level behavior identities) and the level at which behavior is identified can have far-reaching effects on specific high-order thinking processes. The present experiments link a social orientation to behavior-identification level and show that creating a social orientation engages high-level behavior identification. In three experiments, participants were shown behaviors and indicated whether a specified low-level or high-level identification of each behavior matched the way they interpret the behavior. Participants who completed this task while anticipating (vs. not anticipating) social interaction, in the presence (vs. absence) of eye images, or following exposure to social-interaction (vs. control) words indicated more high-level identifications. Participants who completed this task following exposure to privacy-denoting (vs. control) words, however, indicated fewer high-level identifications.

Abstract:Two studies examined whether priming self-schemas relating to successful emotional competency results in better emotional intelligence performance. In the first study participants were randomly assigned to a successful emotional competency self-schema prime condition or a control condition and then completed an ability measure of emotional intelligence (the MSCEIT). Participants in the emotional competency prime condition performed significantly better on the emotional intelligence tasks comprising the MSCEIT than those in the control condition. Participants in the second study were randomly assigned to conditions designed to prime one of the following: 1) success-related aspects of the emotional competency self-schema, 2) motivation-related aspects of the emotional competency self-schema, 3) a general emotional competency schema, or 4) attention to the self as a control condition. Participants primed for emotional competency success showed better emotional intelligence performance as assessed by the MSCEIT compared to the attention to the self control condition. The successful emotional competency prime most influenced strategic emotional functioning. These findings extend knowledge regarding the range of intelligence that can be primed and add to information relating to priming different aspects of the self-schema.

Abstract:What makes you popular at school? And what are the labor market returns to popularity? We investigate these questions using an objective measure of popularity derived from sociometric theory: the number of friendship nominations received from schoolmates, interpreted as a measure of early accumulation of personal social capital. We develop an econometric model of friendship formation and labor market outcomes allowing for partial observation of networks, and provide new evidence on the impact of early family environment on popularity. We estimate that moving from the 20th to 80th percentile of the high-school popularity distribution yields a 10% wage premium nearly 40 years later.

Abstract:Effective social interactions require the ability to evaluate other people's actions and intentions, sometimes only on the basis of such subtle factors as body language, and these evaluative judgments may lead to powerful impressions. However, little is known about the impact of affective body language on evaluative responses in social settings and the associated neural correlates. This study investigated the neural correlates of observing social interactions in a business setting, in which whole-body dynamic stimuli displayed approach and avoidance behaviors that were preceded or not by a handshake and were followed by participants' ratings of these behaviors. First, approach was associated with more positive evaluations than avoidance behaviors, and a handshake preceding social interaction enhanced the positive impact of approach and diminished the negative impact of avoidance behavior on the evaluation of social interaction. Second, increased sensitivity to approach than to avoidance behavior in amygdala and STS was linked to a positive evaluation of approach behavior and a positive impact of handshake. Third, linked to the positive effect of handshake on social evaluation, nucleus accumbens showed greater activity for Handshake than for No-handshake conditions. These findings shed light on the neural correlates of observing and evaluating nonverbal social interactions and on the role of handshake as a way of formal greeting.

Abstract:Social difficulties during adolescence influence life-span health. To elucidate underlying mechanisms, we examined whether a noxious social event, targeted rejection (TR), influences the signaling pathways that regulate inflammation, which is implicated in a number of health problems. For this study, 147 adolescent women at risk for developing a first episode of major depression were interviewed every 6 months for 2.5 years to assess recent TR exposure, and blood was drawn to quantify leukocyte messenger RNA (mRNA) for nuclear factor-κB (NF-κB) and inhibitor of κB (I-κB) and the inflammatory biomarkers C-reactive protein and interleukin-6. Participants had more NF-κB and I-κB mRNA at visits when TR had occurred. These shifts in inflammatory signaling were most pronounced for adolescents high in perceived social status. These findings demonstrate that social rejection upregulates inflammatory gene expression in youth at risk for depression, particularly for those high in status. If sustained, this heightened inflammatory signaling could have implications for life-span health.

Abstract:The ability to understand and predict others' behavior is essential for successful interactions. When making predictions about what other humans will do, we treat them as intentional systems and adopt the intentional stance, i.e., refer to their mental states such as desires and intentions. In the present experiments, we investigated whether the mere belief that the observed agent is an intentional system influences basic social attention mechanisms. We presented pictures of a human and a robot face in a gaze cuing paradigm and manipulated the likelihood of adopting the intentional stance by instruction: in some conditions, participants were told that they were observing a human or a robot, in others, that they were observing a human-like mannequin or a robot whose eyes were controlled by a human. In conditions in which participants were made to believe they were observing human behavior (intentional stance likely) gaze cuing effects were significantly larger as compared to conditions when adopting the intentional stance was less likely. This effect was independent of whether a human or a robot face was presented. Therefore, we conclude that adopting the intentional stance when observing others' behavior fundamentally influences basic mechanisms of social attention. The present results provide striking evidence that high-level cognitive processes, such as beliefs, modulate bottom-up mechanisms of attentional selection in a top-down manner.

Abstract:Estimating another person's subjective confidence is crucial for social interaction, but how this inference is achieved is unknown. Previous research has demonstrated that the speed at which people make decisions is correlated with their confidence in their decision. Here, we show that (i) subjects are able to infer the subjective confidence of another person simply through the observation of their actions and (ii) this inference is dependent upon the performance of each subject when executing the action. Crucially, the latter result supports a model in which motor simulation of an observed action mediates the successful understanding of other minds. We conclude that kinematic understanding allows access to the higher-order cognitive processes of others, and that this access plays a central role in social interactions.

Abstract:Two lines of evidence indicate that there exists a reciprocal inhibitory relationship between opposed brain networks. First, most attention-demanding cognitive tasks activate a stereotypical set of brain areas, known as the task-positive network and simultaneously deactivate a different set of brain regions, commonly referred to as the task negative or default mode network. Second, functional connectivity analyses show that these same opposed networks are anti-correlated in the resting state. We hypothesize that these reciprocally inhibitory effects reflect two incompatible cognitive modes, each of which is directed towards understanding the external world. Thus, engaging one mode activates one set of regions and suppresses activity in the other. We test this hypothesis by identifying two types of problem-solving task which, on the basis of prior work, have been consistently associated with the task positive and task negative regions: tasks requiring social cognition, i.e., reasoning about the mental states of other persons, and tasks requiring physical cognition, i.e., reasoning about the causal/mechanical properties of inanimate objects. Social and mechanical reasoning tasks were presented to neurologically normal participants during fMRI. Each task type was presented using both text and video clips. Regardless of presentation modality, we observed clear evidence of reciprocal suppression: social tasks deactivated regions associated with mechanical reasoning and mechanical tasks deactivated regions associated with social reasoning. These findings are not explained by self-referential processes, task engagement, mental simulation, mental time travel or external vs. internal attention, all factors previously hypothesized to explain default mode network activity. Analyses of resting state data revealed a close match between the regions our tasks identified as reciprocally inhibitory and regions of maximal anti-correlation in the resting state. These results indicate the reciprocal inhibition is not attributable to constraints inherent in the tasks, but is neural in origin. Hence, there is a physiological constraint on our ability to simultaneously engage two distinct cognitive modes. Further work is needed to more precisely characterize these opposing cognitive domains.

Objective: This research examined the psychosocial and personality predictors of observed speeding among young drivers.

Method: Survey and driving data were collected from 42 newly-licensed teenage drivers during the first 18 months of licensure. Speeding (i.e., driving 10 mph over the speed limit; about 16 km/h) was assessed by comparing speed data collected with recording systems installed in participants' vehicles with posted speed limits. Questionnaire data collected at baseline were used to predict speeding rates using random effects regression analyses. For mediation analysis, data collected at baseline and at 6, 12, and 18 months after licensure were used.

Results: Speeding was correlated with elevated g-force event rates, including hard braking and turning (r = 0.335, p < 0.05), but not with crashes and near crashes (r = 0.227; ns). Speeding prevalence increased over time. In univariate analyses speeding was predicted by day vs. night trips, higher sensation seeking, substance use, tolerance of deviance, susceptibility to peer pressure, and number of risky friends. In multivariate analyses the number of risky friends was the only significant predictor of speeding. Perceived risk was a significant mediator of the association between speeding and risky friends.

Conclusion: The findings support the contention that social norms may influence teenage speeding behavior and this relationship may operate through perceived risk.

Abstract:Oxytocin and its receptor (OXTR) play an important role in a variety of social perceptual and affiliative processes. Individual variability in social information processing likely has a strong heritable component, and as such, many investigations have established an association between common genetic variants of OXTR and variability in the social phenotype. However, to date, these investigations have primarily focused only on changes in the sequence of DNA without considering the role of epigenetic factors. DNA methylation is an epigenetic mechanism by which cells control transcription through modification of chromatin structure. DNA methylation of OXTR decreases expression of the gene and high levels of methylation have been associated with autism spectrum disorders (ASD). This link between epigenetic variability and social phenotype allows for the possibility that social processes are under epigenetic control. We hypothesized that the level of DNA methylation of OXTR would predict individual variability in social perception. Using the brain's sensitivity to displays of animacy as a neural endophenotype of social perception, we found significant associations between the degree of OXTR methylation and brain activity evoked by the perception of animacy. Our results suggest that consideration of DNA methylation may substantially improve our ability to explain individual differences in imaging genetic association studies.

Nadine Striepens et al.Proceedings of the National Academy of Sciences, 30 October 2012, Pages 18144-18149

Abstract:The neuropeptide oxytocin (OXT) can enhance the impact of positive social cues but may reduce that of negative ones by inhibiting amygdala activation, although it is unclear whether the latter causes blunted emotional and mnemonic responses. In two independent double-blind placebo-controlled experiments, each involving over 70 healthy male subjects, we investigated whether OXT affects modulation of startle reactivity by aversive social stimuli as well as subsequent memory for them. Intranasal OXT potentiated acoustic startle responses to negative stimuli, without affecting behavioral valence or arousal judgments, and biased subsequent memory toward negative rather than neutral items. A functional MRI analysis of this mnemonic effect revealed that, whereas OXT inhibited amygdala responses to negative stimuli, it facilitated left insula responses for subsequently remembered items and increased functional coupling between the left amygdala, left anterior insula, and left inferior frontal gyrus. Our results therefore show that OXT can potentiate the protective and mnemonic impact of aversive social information despite reducing amygdala activity, and suggest that the insula may play a role in emotional modulation of memory.

Abstract:Observing someone perform an action engages brain regions involved in motor planning, such as the inferior frontal, premotor, and inferior parietal cortices. Recent research suggests that during action observation, activity in these neural regions can be modulated by membership in an ethnic group defined by physical differences. In this study we expanded upon previous research by matching physical similarity of two different social groups and investigating whether likability of an outgroup member modulates activity in neural regions involved in action observation. Seventeen Jewish subjects were familiarized with biographies of eight individuals, half of the individuals belonged to Neo-Nazi groups (dislikable) and half of which did not (likable). All subjects and actors in the stimuli were Caucasian and physically similar. The subjects then viewed videos of actors portraying the characters performing simple motor actions (e.g. grasping a water bottle and raising it to the lips), while undergoing fMRI. Using multivariate pattern analysis (MVPA), we found that a classifier trained on brain activation patterns successfully discriminated between the likable and dislikable action observation conditions within the right ventral premotor cortex. These data indicate that the spatial pattern of activity in action observation related neural regions is modulated by likability even when watching a simple action such as reaching for a cup. These findings lend further support for the notion that social factors such as interpersonal liking modulate perceptual processing in motor-related cortices.

About the Author

Kevin Lewis is a columnist for the Ideas section of the Boston Globe. He has degrees in physics and political science from MIT, has studied and taught organizational behavior at UC Berkeley and Duke, and has worked in high-tech business and finance.